Merocyanine-like thiazole dyes and thermal transfer thereof

ABSTRACT

Useful thermal transfer dyes are thiazole dyes having the formula &lt;IMAGE&gt;  where R1 and R2 are each, independently of the other, hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted phenyl or cyclohexyl or together with the linking nitrogen atom a heterocyclic radical, R3 is hydrogen, halogen, alkyl, substituted or unsubstituted phenyl, benzyl, cyclohexyl, hydroxyl, furyl or thienyl, and A is a cyclohexadienone radical which may be substituted and/or benzofused.

The present invention relates to novel thiazole dyes of the formula I##STR2## where R¹ and R² are identical or different and each is,independently of the other, alkyl, which may be interrupted by from 1 to3 oxygen atoms, alkanoyloxyalkyl or alkoxycarbonyloxyalkyl, which mayeach have up to 18 carbon atoms and be substituted by phenyl, C₁ -C₄-alkylphenyl, C₁ -C₄ -alkoxyphenyl, hydroxyl, cyclohexyl or cyano,hydrogen, unsubstituted or C₁ -C₁₄ -alkyl- or C₁ -C₄ -alkoxy-substitutedphenyl, cyclohexyl or a radical of the formula

    (CH.sub.2 --).sub.k COO--(Y--O--).sub.m (W--O--).sub.v L.sup.1,

where

k is 2, 3 or 4,

m and v are identical or different and each is, independently of theother, 0, 1 or 2,

Y and W are identical or different and each is, independently of theother, C₂ -C₆ -alkylene and L¹ is C₁ -C₄ -alkyl or unsubstituted or C₁-C₄ -alkyl- or C₁ -C₄ -alkoxy-substituted phenyl,

or R¹ and R², together with the linking nitrogen atom, are a 5- or6-membered saturated heterocyclic radical which may contain furtherhetero atoms and be substituted by C₁ -C₆ -alkyl,

R³ is hydrogen, halogen, C₁ -C₈ -alkyl, unsubstituted or C₁ -C₄ -alkyl-or C₁ -C₄ -alkoxy-substituted phenyl, unsubstituted or C₁ -C₄ -alkyl- orC₁ -C₄ -alkoxy-substituted benzyl, cyclohexyl, hydroxyl, furyl orthienyl, and

A is a radical of the formula ##STR3## where L² is hydrogen, fluorine,chlorine, bromine, hydroxyl, nitro C₁ -C₄ -alkyl, cyano, C₁ -C₄-alkyl-sulfonylamino or a radical of the formula COOR¹, CONHR¹, NHCOR¹or NHSO₂ R¹, in each of which R¹ is as defined above, and

L³ is hydrogen, fluorine, chlorine, cyano or a radical of the formulaCONHL⁴, NHCOL⁴, NHCONHL⁴, SO₂ NHL⁴, NHSO₂ L⁴ or COOR¹, where R¹ is asdefined above and L⁴ is in each case alkoxycarbonylphenyl,alkoxycarbonyloxyphenyl, alkanoylphenyl or N-monoalkylcarbamo-vlphenyl,the alkyl moieties in these groups having up to 12 carbon atoms, phenyl,thiazolyl or C₁ -C₁₂ -alkyl, which may be interrupted by from 1 to 3oxygen atoms,

and a process for the thermal transfer of these dyes.

DE-A-3 524 519 discloses dyes which are prepared by oxidative couplingof p-phenylenediamines onto phenols and which find use in the thermaltransfer printing of coated papers.

Similar dyes for the same use, where naphthols are used instead ofphenols, are described in EP-A-227 096 and U.S. Pat. No. 4,769,360.

It is an object of the present invention to provide new merocyanine-likedyes which have a heterocyclic radical. The new dyes should haveadvantageous application properties.

We have found that this object is achieved by the thiazole dyes of theformula I described at the beginning.

Any alkyl appearing in the abovementioned formula is eitherstraight-chain or branched

R¹, R², R³, L¹, L² and L⁴ are each for example methyl, ethyl, propyl,isopropyl, butyl, isobutyl, secbutyl or tert-butyl.

R¹, R², R³ and L⁴ may each also be for example pentyl, isopentyl,neopentyl, tert-pentyl, hexyl, 2-methylpentyl, heptyl, octyl,2-ethylhexyl or isooctyl.

R¹, R² and L⁴ may each also be for example nonyl, isononyl, decyl,isodecyl, undecyl or dodecyl.

R¹ and R² may each also be for example tridecyl, isotridecyl,tetradecyl, pentadecyl, hexadecyl, heptadecyl or octadecyl (thedesignations isooctoyl, isononyl, isodecyl and isotridecyl are trivialnames which are derived from the alcohols obtained by the oxo process(cf. on this point Ullmanns Encyklopadie der technischen Chemie, 4thedition, volume 7, pages 215 to 217, and volume 11, pages 435 and 436)),2-methoxyethyl, 2-ethoxyethyl, 2-propoxyethyl, 2-butoxyethyl, 2- or3-methoxypropyl, 2- or 3-ethoxypropyl, 2- or 3-propoxypropyl, 2- or3-butoxypropyl, 4-methoxybutyl, 4-ethoxybutyl, 4-butoxybutyl,8-butoxyoctyl, 2-cyanoethyl, 3-cyanopropyl, 4-cyanobutyl,2-hydroxyethyl, 5-hydroxynonyl, 4-(2-methylphenyl)butyl, 3-phenylbutyl,2-methoxybenzyl, ##STR4##

R¹, R², R³ and L¹ may each also be for example phenyl, 2-, 3- or4-methylphenyl, 2- or 4-isopropylphenyl, 2-butylphenyl, 2-, 3- or4-methoxyphenyl, 2-propoxyphenyl, 4-butoxyphenyl or 2-(but-2-oxy)phenyl.

When R¹ and R² together with the linking nitrogen atom are a 5- or6-membered saturated heterocyclic radical, it may be substituted by C₁-C₆ -alkyl and contain further hetero atoms, for example anothernitrogen atom or oxygen.

Individual heterocyclic radicals are for example pyrrolidino,piperidino, morpholino, piperazino, 2-methylpyrrolidino,3-butylpyrrolidino,4-ethylpiperidino, 2,6-dimethylpiperidino,2-(pent-2-yl)piperidino, 2-methylmorpholino, 3-ethyl-5-methylmorpholino,N-methylpiperazino, N-ethylpiperazino,3-butylhexahydropyrimidin-1-yl or3,6-dimethylhexahydropyrimidin-1-yl.

L⁴ may also be for example thiazol-2-yl, thiazol-5-yl,4-propanoylphenyl, 4-pentanoylphenyl, 4-(4-methylpentanoyl)phenyl,4-ethoxycarbonylphenyl, 4-propoxycarbonylphenyl,4-butoxycarbonylpheny1,4-pentyloxycarbonylphenyl or 4-(N-ethyl- orN-hexyl-carbamoyl)phenyl.

Preference is given to thiazole dyes of the formula II ##STR5## where R¹and R² are each, independently of the other, alkyl, which may beinterrupted by from to 3 oxygen atoms, alkanoyloxyalkyl oralkoxycarbonylalkyl, which may each have up to 12 carbon atoms, ortogether with the linking nitrogen atom, a 5- or 6-membered saturatedheterocyclic radical which may contain further hetero atoms,

L² is hydrogen or a radical of the formula CONHR¹, NHCOR¹ or NHSO₂ R¹,where R¹ is in each case as defined above, and

L³ is a radical of the formula CONHL⁴, NHCOL⁴, SO₂ NHL⁴ or NHSO₂ L⁴,

where R³ and L⁴ are each as defined above.

Particular preference is given to thiazole dyes of the formula IIa##STR6## where R¹ and R² are each, independently of the other, C₁ -C₈-alkyl, which may be interrupted by an oxygen atom, or together with thelinking nitrogen atom pyrrolidino, piperidino or morpholino,

R³ is phenyl, which may be substituted by methyl or methoxy, benzyl,which may be substituted by methyl or methoxy, or thienyl, and

L³ is a radical of the formula CONHL⁴, NHCOL⁴, SO₂ NHL⁴ or NHSO₂ L⁴,

where L⁴ is C₁ -C₈ -alkyl, which may be interrupted by an oxygen atom,phenyl, thiazolyl, 4-(C₁ -C₈ -alkoxycarbonyl)phenyl or 4-[N-(C₁ -C₈-monoalkyl)carbamoyl]phenyl.

The thiazole dyes of the formula I according to the present inventionare prepared in a conventional manner.

For instance, a thiazole of the formula III ##STR7## where R¹, R² and R³are each as defined above, is reacted with a quinone derivative of theformula IVa or IVb ##STR8## where L² and L³ are each as defined above(variant A--see for example Houben-Weyl, Methoden der OrganischenChemie, volume Quinones II, pages 262 to 265 and also 299 ff). Thequinones IVa and IVb are obtained by oxidation of the correspondingp-amino compounds.

However, it is also possible to nitrosate the thiazole III and then tocondense the nitroso compound with a phenol of the formula Va or anaphthol of the formula Vb ##STR9## where L² and L³ are each as definedabove (variant B--see for example DE-A-3 716 656).

It is a further object of the present invention to provide a new processfor the thermal transfer of dyes.

In the thermal transfer printing process, a transfer sheet whichcontains a thermally transferable dye in one or more binders, with orwithout suitable assistants, on a substrate is heated from the back witha heat source in short heating pulses (duration: fractions of a second),as a result of which the dye migrates out of the transfer sheet anddiffuses into the surface coating of a receiving medium. The essentialadvantage of this process is that the amount of dye to be transferred(and hence the color gradation) is easy to control by adjusting theenergy supplied to the heat source.

In general, color recording is carried out using the three subtractiveprimaries yellow, magenta and cyan (with or without black). To ensureoptimal color recording, the dyes must have the following properties:

ready thermal transferability,

little tendency to migrate within or out of the surface coating of thereceiving medium at room temperature,

high thermal and photochemical stability and also resistance to moistureand chemical substances,

suitable hues for subtractive color mixing,

a high molar absorption coefficient,

resistance to crystallization on storage of the transfer sheet,

ready industrial availability.

Experience shows that these requirements are very difficult to meet allat once.

For this reason most of the existing thermal transfer printing dyes fallshort of the postulated ideal.

We have found that this object is achieved, and that the transfer ofmerocyanine-like dyes from a transfer to plastic-coated paper with theaid of an energy source is possible to advantageous effect, on using atransfer on which there is or are situated one or more thiazole dyes ofthe formula I ##STR10## where R¹ and R² are identical or different andeach is, independently of the other, alkyl, which may be interrupted byfrom 1 to 3 oxygen atoms, alkanoyloxyalkyl or alkoxycarbonyloxyalkyl,which may each have up to 18 carbon atoms and be substituted by phenyl,C₁ -C₄ -alkylphenyl, C₁ -C₄ -alkoxyphenyl, hydroxyl, cyclohexyl orcyano, hydrogen, unsubstituted or C₁ -C₄ -alkyl- or C₁ -C₄-alkoxy-substituted phenyl, cyclohexyl or a radical of the formula

    (CH.sub.2 --).sub.k COO--(Y--O--).sub.m (W--O--).sub.v L.sup.1,

where

k is 2, 3 or 4,

m and v are identical or different and each is, independently of theother, 0, 1 or 2,

Y and W are identical or different and each is, independently of theother, C₂ -C₆ -alkylene and

L¹ is C₁ -C₄ -alkyl or unsubstituted or C₁ -C₄ -alkyl or C₁ -C₄-alkoxy-substituted phenyl,

or R¹ and R², together with the linking nitrogen atom, are a 5- or6-membered saturated heterocyclic radical which may contain furtherhetero atoms and be substituted by C₁ -C₆ -alkyl,

R³ is hydrogen, halogen, C₁ -C₈ -alkyl, unsubstituted or C₁ -C₄ -alkyl-or C₁ -C₄ -alkoxy-substituted phenyl, unsubstituted or C₁ -C₄ -alkyl- orC₁ -C₄ -alkoxy-substituted benzyl, cyclohexyl, hydroxyl, furyl orthienyl, and

A is a radical of the formula ##STR11## where L² is hydrogen, fluorine,chlorine, bromine, hydroxyl, nitro, C₁ -C₄ -alkyl, cyano, C₁ -C₄-alkylsulfonylamino or a radical of the formula COOR¹, CONHR¹, NHCOR¹ orNHSO₂ R¹, in each of which R¹ is as defined above, and

L³ is hydrogen, fluorine, chlorine, cyano or a radical of the formulaCONHL⁴, NHCOL⁴, NHCONHL⁴, SO₂ NHL⁴, NHSO₂ L⁴ or COOR¹, where R¹ is asdefined above and L⁴ is in each case alkoxycarbonylphenyl,alkoxycarbonyloxyphenyl, alkanoylphenyl or N-monoalkylcarbamoylphenyl,the alkyl moieties in these groups having up to 12 carbon atoms, phenyl,thiazolyl or C₁ -C₁₂ -alkyl, which may be interrupted by from 1 to 3oxygen atoms.

Preference is given to the process involving the dyes of theabovementioned formula II, in particular the dyes of the abovementionedformula IIa.

A suitable energy source for the process according to the presentinvention is for example a thermal printing head or else a laser. Theuse of a thermal printing head is preferred.

To prepare the transfer required for the novel process, the dyes areincorporated into a suitable organic solvent, e.g. chlorobenzene,isobutanol, methyl ethyl ketone, methylene chloride, toluene,tetrahydrofuran or a mixture thereof, together with one or more bindersand with or without the addition of other auxiliaries to form a printingink, in which the dye is preferably present in a molecularly dispersed,i.e. dissolved, form. The printing ink is applied to the inert substrateby knife coating and the coating is dried in air.

Suitable binders are all resins and polymer materials which are solublein organic solvents and capable of binding the dye to the inertsubstrate in such a way that it will not rub off. Preference is given tothose binders which, after the printing ink has dried in air, hold thedye in the form of a clear, transparent film without visiblecrystallization of the dye.

Examples of such binders are cellulose derivatives, e.g.methylcellulose, ethylcellulose, ethylhydroxyethylcellulose,hydroxypropylcellulose, cellulose acetate or cellulose acetobutyrate,starch, alginates, alkyd resins, vinyl resins, polyvinyl alcohol,polyvinyl acetate, polyvinyl butyrate and polyvinylpyrrolidones. It isalso possible to use polymers and copolymers of acrylates or derivativesthereof, such as polyacrylic acid, polymethyl methacrylate orstyrene-acrylate copolymers, polyester resins, polyamide resins,polyurethane resins or natural CH resins, such as gum arabic. Othersuitable binders are described for example in DE-A-3 524 519.

The preferred binders are ethylcellulose, ethylhydroxyethylcellulose,polyvinyl butyrate and polyvinyl acetate.

The ratio of binder to dye is preferably within the range from 1:1 to5:1 by weight.

Suitable assistants are for example release agents as described inEP-A-227 092, EP-A-192 435 and the patent applications cited therein andalso in particular organic additives which stop the transfer dye fromcrystallizing in the course of storage or heating of the inked ribbon,for example cholesterol or vanillin.

Inert substrates are for example tissue, blotting or parchment paper orplastics films of high heat stability, for example uncoated ormetal-coated polyester, polyamide or polyimide. The inert substrate mayadditionally be coated on the side facing the energy source with alubricant, or slipping, layer in order to prevent adhesion of the energysource to the substrate material. Suitable lubricants are described forexample in EP-A-216 483 and EP-A-227 095. The thickness of the substrateis in general from 3 to 30 μm, preferably from 5 to 10 μm.

Suitable dye receiver layers are basically all temperature stableplastic layers having an affinity for the dyes to be transferred andpreferably glass transition temperatures (Tg) within the range 50°C.<Tg<100° C., e.g. modified polycarbonates and polyesters. Suitablerecipes for the receiver layer composition are described in detail forexample in EP-A-227 094, EP-A-133 0 12, EP-A-133 011, EP-A-111 004,JP-A-199 997/1986, JP-A-283 595/1986, JP-A-237 694/1986 and JP-A-127392/1986.

Transfer is preferably effected by means of a thermal printing headwhich must be heatable to ≧300° C. for dye transfer to take place withinthe time interval t: 0<t<15 msec. On heating, the dye migrates out ofthe transfer sheet and diffuses into the surface coat of the receivingmedium.

Compared with the dyes used in existing processes, the novel dyestransferred in the process according to the present invention are ingeneral notable for improved migration properties in the receivingmedium at room temperature, readier thermal transferability, readierindustrial availability, better resistance to moisture and chemicalsubstances, higher color strength, better solubility, higher lightfastness and in particular better purity of hue.

The Examples which follow further illustrate the invention. Percentagesare by weight, unless otherwise stated.

Preparation of the Thiazole Dyes Example of the Synthesis by Variant A##STR12##

5.9 g of 2,6-dichloroquinonechlorimide (paste about 90% strength) and7.3 g of 2-diethylamino-4-phenylthiazole were dissolved in 100 ml ofglacial acetic acid at room temperature. The solution was subsequentlystirred for 30 minutes, in the course of which the temperature rose to35° C., and ice-water was then added. The resulting oily phase wasdecanted off, and the solution was diluted with ice-water and adjustedto pH 7.2 with 10% strength sodium hydroxide solution.

The blue precipitate which had formed was filtered off with suction,washed with water and dried in a vacuum drying cabinet at 30° C. Yield:6.2 g of crude material

Column chromatography over silica gel (mobile phase: 8:2 (v/v)toluene/ethyl acetate) gave 3 g of a spectrally pure product. λ_(max)(methylene chloride): 617 nm.

Example of the Synthesis by Variant B ##STR13##

To 12.95 g of 1-hydroxy-8-N-(3-methoxypropyl)naphthamide in 100 ml ofacetic anhydride was added an equimolar amount of 5-nitroso2-diisopropylaminothiazole, dissolved in 150 ml of methylene chloride,and the mixture was heated up with distillative removal of the methylenechloride. By the time 100° C. was reached, the reaction had ended. Themixture was then cooled down with stirring, 200 ml of methylene chloridewere added at 40° C., and acetic anhydride was destroyed by the additionof hot water (60° C.). This was followed by a further 15 minutes'stirring under reflux at 45°-50° C. The phases were then separated in aseparating funnel, and the organic phase was concentrated in a rotaryevaporator. 400 ml of water were added to the residue, and the aqueousmixture was carefully neutralized with sodium bicarbonate, the targetproduct being obtained in the form of an oil.

1st purification: The oil was dissolved in methylene chloride and thesolution was poured through silica gel. Yield: 9.3 g.

2nd purification: Column chromatography, silica gel Mobile phase: ethylacetate Yield: 3.2 g of spectrally pure product. λ_(max)(tetrahydrofuran): 619 nm.

Transfer of the Thiazole Dyes

To be able to test the transfer characteristics of the dyes in aquantitative and simple manner, the heat transfer process was carriedout with large hotplates instead of a thermal printing head, thetransfer temperature being varied within the range 70° C.<T<120° C. andthe transfer time being set at 2 minutes.

α) General Recipe for Coating the Substrates With Dye

1 g of binder were dissolved in 8 ml (8:2 v/v) of toluene/ethanol atfrom 40° to 50° C. A solution of 0.25 g of dye in 5 ml oftetrahydrofuran was added by stirring. The print paste thus obtained wasapplied with an 80 μm knife to a sheet of polyester film (thickness:6-10 μm) and dried with a hairdryer.

β) Testing of Thermal Transferability

The dyes used were tested in the following manner:

The polyester sheet donor containing the dye under test in the coatedfront was placed face down on a sheet of commercial Hitachi Color VideoPrint Paper (receiver) and pressed down. Donor/receiver were thenwrapped in aluminum foil and heated between two hot plates at differenttemperatures T (within the temperature range 70° C.<T<120° C.). Theamount of dye diffusing into the bright plastic layer of the receiver isproportional to the optical density (=absorbance A). The latter wasdetermined photometrically. If the logarithm of the absorbance A of thecolored receiver papers measured within the temperature range from 80°to 110° C. is plotted against the corresponding reciprocal of theabsolute temperature, the result is a straight line whose slope givesthe activation energy ΔE_(T) for the transfer experiment: ##EQU1##

To complete the characterization, it is additionally possible to inferfrom the plots the temperature T*[° C] at which, in the absence of anyindication to the contrary, the absorbance A of the colored receiverpapers attains the value 1.

The dyes listed in the tables which follow were processed according toα), and the resulting dye-coated substrates were tested in respect oftheir transfer characteristics according to β). Tables 1 and 2 list ineach case the heat transfer parameters T* and ΔE_(T), the absorptionmaxima of the dyes λ_(max) (measured in methylene chloride), and thebinders used.

The following abbreviations apply:

Br=binder (EC=ethyl cellulose, EHEC=ethylhydroxyethylcelluloseAC=cellulose acetobutyrate, MIX=mixture of polyvinyl butyrate andethylcellulose in a weight ratio of 2:1)

The dyes in Tables 1, 11 and 12 were synthesized by variant A.

The dyes in Tables 2 to 10 were synthesized by variant B. Tables 3 to 10contain the absorption maxima λ_(max) (measured in tetrahydrofuran), theR_(f) value of the dyes and the mobile phase used in the thin layerchromatography (T=toluene; EA=ethyl acetate - The stated mixing ratiosare by volume.). TLC was done on aluminum sheets from Merck (Darmstadt)bearing the designation: silica gel 60 F 254, 0.2 mm, article No. 5554.

                                      TABLE 1                                     __________________________________________________________________________     ##STR14##                                                                     Example No.                                                                          R.sup.1                                                                          R.sup.2                                                                           R.sup.3                                                                             R.sup.4                                                                          B     Br                                                                               λ.sub.max [nm]                                                              T* [°C.]                                                                    ##STR15##                          __________________________________________________________________________    1      C.sub.2 H.sub.5                                                                  C.sub.2 H.sub.5                                                                   C.sub.6 H.sub.5                                                                     3-Cl                                                                             Cl    EC 617  82   24                                  2      C.sub.2 H.sub.5                                                                  C.sub.2 H.sub.5                                                                   Thien-2-yl                                                                          H  NHCOCH.sub.3                                                                        MIX                                                                              654  86   16                                  __________________________________________________________________________

                                      TABLE 2                                     __________________________________________________________________________     ##STR16##                                                                     No. Example                                                                        R.sup.1                                                                             R.sup.2                                                                               R.sup.3                                                                             R.sup.4                                                                          B                Br                                                                               [nm]λ.sub.max                                                             T* [°C.]                                                                    ##STR17##            __________________________________________________________________________    3    CH(CH.sub.3).sub.2                                                                  CH(CH.sub.3).sub.2                                                                    C.sub.6 H.sub.5                                                                     H  CONHC.sub.7 H.sub.15                                                                           MIX                                                                              635                                                                              81   20                    4    C.sub.2 H.sub.5                                                                     C.sub.2 H.sub.5                                                                       Thien-3-yl                                                                          H  CONHC.sub.7 H.sub.15                                                                           MIX                                                                              644                                                                              82   15                    5    C.sub.2 H.sub.5                                                                     CH.sub.3 OC.sub.3 H.sub.6                                                             Thien-3-yl                                                                          H  CONHC.sub.7 H.sub.15                                                                           MIX                                                                              643                                                                              85   14                    6    C.sub.2 H.sub.5                                                                     H.sub.5 C.sub.2 (OH.sub.4 C.sub.2).sub.3                                              C.sub.6 H.sub.5                                                                     H                                                                                 ##STR18##       EC 670                                                                              90   13                    7    C.sub.2 H.sub.5                                                                     C.sub.2 H.sub.5                                                                       C.sub.6 H.sub.5                                                                     H  CONHC.sub.2 H.sub.5                                                                            EC 627                                                                              84   18                    8    C.sub.2 H.sub.5                                                                     C.sub.2 H.sub.5                                                                       C.sub.6 H.sub.5                                                                     H                                                                                 ##STR19##       EC 655                                                                              104  20                    __________________________________________________________________________

                  TABLE 3                                                         ______________________________________                                         ##STR20##                                                                    Example                                Mobile                                 No.    R                 λ.sub.max [nm]                                                                  R.sub.f                                                                            phase                                  ______________________________________                                         9                                                                                    ##STR21##        644      0.36 T:E 3:2                                10                                                                                    ##STR22##        620      0.22 T:E 9:1                                11                                                                                    ##STR23##        645      0.15 E                                      12                                                                                    ##STR24##        620      0.24 T:E 8:2                                13     C.sub.2 H.sub.4 OCH.sub.3                                                                       619      0.17 E                                      14                                                                                    ##STR25##        620      0.42 T:E 8:2                                15                                                                                    ##STR26##        620      0.36 T:E 8:2                                16     C.sub.18 H.sub.37 620      0.32 T:E 9:1                                ______________________________________                                    

                  TABLE 4                                                         ______________________________________                                         ##STR27##                                                                    Example                               Mobile                                  No.    R              λ.sub.max [nm]                                                                   R.sub.f                                                                             phase                                   ______________________________________                                        17     C.sub.2 H.sub.5                                                                              618       0.32  E                                       18     C.sub.2 H.sub.4 OCH.sub.3                                                                    618       0.17  E                                       19     C.sub.3 H.sub.6 OCH.sub.3                                                                    618       0.16  E                                       20                                                                                    ##STR28##     618       0.48  E                                       21                                                                                    ##STR29##     618       0.44  T:E 3:2                                 22                                                                                    ##STR30##     618       0.47  T:E 3:2                                 23     C.sub.18 H.sub.37                                                                            618       0.43  T:E 3:2                                 24                                                                                    ##STR31##     618       0.46  T:E 3:2                                 25                                                                                    ##STR32##     643       0.096 E                                       ______________________________________                                    

                  TABLE 5                                                         ______________________________________                                         ##STR33##                                                                    Example No.                                                                            R           λ.sub.max [nm]                                                                  R.sub.f                                                                             Mobile phase                              ______________________________________                                        26       C.sub.2 H.sub.5                                                                           620      0.22  E                                         27       C.sub.2 H.sub.4 OCH.sub.3                                                                 621      0.125 E                                         28                                                                                      ##STR34##  621      0.32  T:E 3:2                                   29                                                                                      ##STR35##  647      0.07  E                                         ______________________________________                                    

                  TABLE 6                                                         ______________________________________                                         ##STR36##                                                                    Example                 λ.sub.max                                      No.    R                [nm]  R.sub.f                                                                             Mobile phase                              ______________________________________                                        30     C.sub.2 H.sub.5                                                                              636     0.17  E                                         31     C.sub.2 H.sub.4 OCH.sub.3                                                                    636      0.098                                                                              E                                         32     C.sub.3 H.sub.6 OCH.sub.3                                                                    636     0.14  E                                         33                                                                                    ##STR37##     636     0.36  E                                         34                                                                                    ##STR38##     637     0.43  T:E 3:2                                   35                                                                                    ##STR39##     637     0.40  T:E 3:2                                   36     C.sub.18 H.sub.37                                                                            637     0.46  T:E 3:2                                   37                                                                                    ##STR40##     637     0.37  T:E 3:2                                   38                                                                                    ##STR41##     675     0.08  E                                         ______________________________________                                    

                  TABLE 7                                                         ______________________________________                                         ##STR42##                                                                    Example               λ.sub.max                                        No.    R              [nm]    R.sub.f                                                                             Mobile phase                              ______________________________________                                        39     C.sub.2 H.sub.5                                                                              622     0.12  E                                         40     C.sub.2 H.sub.4 OCH.sub.3                                                                    622      0.068                                                                              E                                         41     C.sub.3 H.sub.6 OCH.sub.3                                                                    622     0.05  E                                         42                                                                                    ##STR43##     622     0.26  E                                         43                                                                                    ##STR44##     623     0.14  T:E 3:2                                   44                                                                                    ##STR45##     622     0.21  T:E 3:2                                   45     C.sub.18 H.sub.37                                                                            622     0.23  T:E 3:2                                   46                                                                                    ##STR46##     622     0.18  T:E 3:2                                   47                                                                                    ##STR47##     649     0.04  E                                         ______________________________________                                    

                  TABLE 8                                                         ______________________________________                                         ##STR48##                                                                    Example               λ.sub.max                                        No.    R              [nm]    R.sub.f                                                                             Mobile phase                              ______________________________________                                        48     C.sub.2 H.sub.5                                                                              644     --    --                                        49     C.sub.2 H.sub.4 OCH.sub.3                                                                    644     0.14  E                                         50     C.sub.3 H.sub.6 OCH.sub.3                                                                    643     0.21  E                                         51                                                                                    ##STR49##     645     0.57  E                                         52                                                                                    ##STR50##     646     0.70  E                                         53                                                                                    ##STR51##     645     0.63  E                                         54     C.sub.18 H.sub.37                                                                            637     0.68  E                                         55                                                                                    ##STR52##     644     0.87  E                                         ______________________________________                                    

                  TABLE 9                                                         ______________________________________                                         ##STR53##                                                                    Example               λ.sub.max                                        No.    R              [nm]    R.sub.f                                                                             Mobile phase                              ______________________________________                                        56     C.sub.2 H.sub.5                                                                              652     --    --                                        57     C.sub.2 H.sub.4 OCH.sub.3                                                                    652      0.098                                                                              E                                         58     C.sub.3 H.sub.6 OCH.sub.3                                                                    653     0.09  E                                         59                                                                                    ##STR54##     653     0.42  E                                         60                                                                                    ##STR55##     653     0.31  T:E 3:2                                   61                                                                                    ##STR56##     653     0.25  T:E 3:2                                   62     C.sub.18 H.sub.37                                                                            652     0.33  T:E 3:2                                   63                                                                                    ##STR57##     652     0.29  T:E 3:2                                   64                                                                                    ##STR58##     691     --    --                                        ______________________________________                                    

                  TABLE 10                                                        ______________________________________                                         ##STR59##                                                                    Example               λ.sub.max                                        No.    R              [nm]    R.sub.f                                                                             Mobile phase                              ______________________________________                                        65     C.sub.2 H.sub.5                                                                              653     0.27  E                                         66     C.sub.2 H.sub.4 OCH.sub.3                                                                    654     0.10  E                                         67                                                                                    ##STR60##     655     0.35  T:E 3:2                                   ______________________________________                                    

                                      TABLE 11                                    __________________________________________________________________________     ##STR61##                                                                    Example No.                                                                          R.sup.1                                                                          R.sup.2                                                                          R.sup.3                                                                            R.sup.4                                                                              B λ.sub.max [nm]                                                               Solvent                                      __________________________________________________________________________    68     C.sub.2 H.sub.5                                                                  C.sub.2 H.sub.5                                                                  2-Thienyl                                                                          3-NHCOCH.sub.3                                                                       H 655   Ethanol                                      69     C.sub.2 H.sub.5                                                                  C.sub.2 H.sub.5                                                                  2-Thienyl                                                                          3-NHCOCH.sub.3                                                                       H 654   Methylene chloride                           __________________________________________________________________________

                                      TABLE 12                                    __________________________________________________________________________     ##STR62##                                                                    Example No.                                                                          R.sup.1                                                                          R.sup.2                                                                          R.sup.3    R.sup.4                                                                          B λ.sub.max [nm]                                                               Solvent                                    __________________________________________________________________________    70     C.sub.2 H.sub.5                                                                  C.sub.2 H.sub.5                                                                  C.sub.6 H.sub.5                                                                          3-Cl                                                                             Cl                                                                              624   Dimethylformamide                          71     C.sub.2 H.sub.5                                                                  C.sub.2 H.sub.5                                                                  C.sub.6 H.sub.5                                                                          3-Cl                                                                             Cl                                                                              617   Methylene chloride                         72     C.sub.2 H.sub.5                                                                  C.sub.2 H.sub.5                                                                  C.sub.6 H.sub.5                                                                          3-Cl                                                                             Cl                                                                              626, 660                                                                            Ethanol                                    73     C.sub.2 H.sub.5                                                                  C.sub.2 H.sub.5                                                                   ##STR63## 3-Cl                                                                             Cl                                                                              622   Tetrahydrofuran                            __________________________________________________________________________

The dyes listed below in Tables 13 and 14 are likewise highly suitablefor the diffusion-controled thermal transfer printing of coated papers.

                                      TABLE 13                                    __________________________________________________________________________     ##STR64##                                                                    Example No.                                                                          R.sup.1 R.sup.2  R.sup.3    R.sup.4 B             Color                __________________________________________________________________________    74     C.sub.2 H.sub.5                                                                       CH(CH.sub.3).sub.2                                                                     C.sub.6 H.sub.5                                                                          H       CONHC.sub.2 H.sub.5                                                                         Cyan                 75     C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                                                        C.sub.6 H.sub.5                                                                          H       CONHC.sub.4 H.sub.9                                                                         Cyan                 76     C.sub.4 H.sub.9                                                                       C.sub.4 H.sub.9                                                                        C.sub.6 H.sub.5                                                                          H       CONHC.sub.6 H.sub.5 COOC.sub.2                                                H.sub.5       Cyan                 77     C.sub.3 H.sub.7                                                                       C.sub.3 H.sub.7                                                                        Thien-2-yl H       CONHC.sub.2 H.sub.5                                                                         Turquoise            78     C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                        Thien-3-yl H       CONHC.sub.3 H.sub.7                                                                         Cyan                 79     C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                        Thien-3-yl H       CONHC.sub.6 H.sub.4 COC.sub.5                                                 C.sub.11      Cyan                 80     C.sub.2 H.sub.5                                                                       C.sub.5 H.sub.11                                                                       Thien-3-yl H       NHCOC.sub.2 H.sub.5                                                                         Cyan                 81     C.sub.4 H.sub.9                                                                       CH(CH.sub.3).sub.2                                                                     C.sub.6 H.sub.5                                                                          H       CONHC.sub.6 H.sub.4 CONHC.sub.5                                                H.sub.11     Cyan                 82     C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                        C.sub.6 H.sub.5                                                                          2-NHSO.sub.2 CH.sub.3                                                                 CONHC.sub.2 H.sub.5                                                                         Cyan                 83     C.sub.2 H.sub.4 CN                                                                    C.sub.4 H.sub.9                                                                         ##STR65## H       CONHC.sub.6 H.sub.4 OCOC.sub.4                                                H.sub.9       Turquoise            84     C.sub.3 H.sub.7                                                                       C.sub.2 H.sub.5                                                                         ##STR66## H       CONHC.sub.3 H.sub.7                                                                         Cyan                 85     C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                                                         ##STR67## H       CONH(C.sub.2 H.sub.4 O).sub.2                                                 C.sub.2 H.sub.5                                                                             Cyan                 86     C.sub.4 H.sub.9 OC.sub.2 H.sub.5                                                      C.sub.4 H.sub.9                                                                        C.sub.6 H.sub.5                                                                          H       NHCOC.sub.3 H.sub.6 OC.sub.2                                                  H.sub.5       Cyan                 87     C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9 OC.sub.3 H.sub.6                                                       Thien-3-yl H       CONHC.sub.3 H.sub.6 OC.sub.2                                                  H.sub.4 OC.sub.6 H.sub.5                                                                    Cyan                 88     C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                                                        C.sub.6 H.sub.5                                                                          2-NHCOCH.sub.3                                                                        CONHC.sub.3 H.sub.6 OCH.sub.3                                                               Cyan                 89     C.sub.2 H.sub.4 CO.sub.2 C.sub.2 H.sub.5                                              C.sub.3 H.sub.7                                                                        C.sub.6 H.sub.5                                                                          H       CONHC.sub.6 H.sub.4 CO.sub.2                                                  C.sub.3 H.sub.7                                                                             Cyan                 90     C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5 O.sub.2 CC.sub.2 H.sub.4                                               Thien-3-yl H       NHCOC.sub.6 H.sub.4 CO.sub.2                                                  C.sub.8 H.sub.17                                                                            Blue                 91     C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                                                        Benzyl     H       CONHC.sub.4 H.sub.9                                                                         Blue                 92     C.sub.4 H.sub.9                                                                       C.sub.4 H.sub.9                                                                        C.sub.6 H.sub.5                                                                          H       CO.sub.2 C.sub.4 H.sub.9                                                                    Cyan                 93     CH.sub.3 OC.sub.3 H.sub.6                                                             C.sub.3 H.sub.7                                                                         ##STR68## H       CN            Blue                 94     C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                                                        C.sub.6 H.sub.5                                                                          H       CONHC.sub.6 H.sub.4 CONHC.sub.3                                                H.sub.7      Cyan                 95     C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                                                        C.sub.6 H.sub.5                                                                          H       NO.sub.2      Cyan                 96     C.sub.2 H.sub.4 CO.sub.2 C.sub.2 H.sub.5                                              C.sub.4 H.sub.9                                                                        Thien-3-yl 2-CN    CONHCH.sub.3  Cyan                 97     C.sub.3 H.sub.7                                                                       C.sub.2 H.sub.5                                                                        C.sub.6 H.sub.5                                                                          5-CONHC.sub.2 H.sub.5                                                                 H             Blue                 98     C.sub.4 H.sub.9                                                                       C.sub.4 H.sub.9                                                                        Thien-3-yl 5-NHCOC.sub.2 H.sub.5                                                                 H             Blue                 99     C.sub.3 H.sub.7                                                                       C.sub.2 H.sub.5                                                                         ##STR69## 2-CO.sub.2 C.sub.3 H.sub.7                                                            CONHC.sub.5 H.sub.11                                                                        Cyan                 __________________________________________________________________________

                                      TABLE 14                                    __________________________________________________________________________    Example No.                                                                          R.sup.1 R.sup.2                                                                              R.sup.3    R.sup.4 B                 Color              __________________________________________________________________________    100    C.sub.4 H.sub.9                                                                       C.sub.4 H.sub.9 OC.sub.3 H.sub.6                                                     C.sub.6 H.sub.5                                                                          2-NO.sub.2                                                                            CONHC.sub.4 H.sub.9                                                                             Cyan               101    C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                                                      C.sub.6 H.sub.5                                                                          2-NHCOCH.sub.3                                                                        SO.sub.2 NHCH.sub.3                                                                             Cyan               102    C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                                                      C.sub.6 H.sub.5                                                                          H       SO.sub.2 NHC.sub.2 H.sub.5                                                                      Cyan               103    C.sub.2 H.sub.5                                                                       C.sub.3 H.sub.7                                                                      Thien-3-yl H       SO.sub.2 NH(CH.sub.2).sub.2                                                   C.sub.6 H.sub.5   Cyan               104    C.sub.3 H.sub.7                                                                       C.sub.3 H.sub.7                                                                      C.sub.6 H.sub.5                                                                          2-NHCOCH.sub.3                                                                        CN                Cyan               105    C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                                                      Thien-2-yl H       Cl                Blue               106    C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                                                      C.sub.6 H.sub.5                                                                          5-NHCOCH.sub.3                                                                        SO.sub.2 NHC.sub.2 H.sub.5                                                                      Cyan               107    C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                      Thien-3-yl 2-Cl                                                                                   ##STR70##        Cyan               108    C.sub. 4 H.sub.9                                                                      C.sub.6 H.sub.13                                                                     C.sub.6 H.sub.5                                                                          2-OH    NHCON(C.sub.4 H.sub.9).sub.2                                                                    Cyan               109    C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                      C.sub.6 H.sub.5                                                                          H       NHSO.sub.2 C.sub.4 H.sub.9                                                                      Cyan               110    C.sub.4 H.sub.9                                                                       C.sub.3 H.sub.7                                                                      Thien-2-yl H                                                                                      ##STR71##        Cyan               111    C.sub.2 H.sub.5                                                                       C.sub.2 H.sub.5                                                                      C.sub.6 H.sub.5                                                                          5-NHSO.sub.2 CH.sub.3                                                                 CN                Cyan               112    C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                                                      C.sub.6 H.sub.5                                                                          4-Cl    NHSO.sub.2 C.sub.2 H.sub.5                                                                      Cyan               113    C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                       ##STR72## H                                                                                      ##STR73##        Cyan               __________________________________________________________________________     ##STR74##                                                                    Example No.                                                                          R.sup.1 R.sup.2                                                                              R.sup.3    R.sup.4 B                 Color              __________________________________________________________________________    114    C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                      C.sub.6 H.sub.5                                                                          H       NHCOCH.sub.3      Blue               115    C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                      C.sub.6 H.sub.5                                                                          H       NHSO.sub.2 C.sub.2 H.sub.5                                                                      Blue               116    C.sub.3 H.sub.7                                                                       C.sub.4 H.sub.9                                                                      C.sub.6 H.sub.5                                                                          2-NHSO.sub.2 C.sub.2 H.sub.5                                                          CONHC.sub.2 H.sub.5                                                                             Cyan               117    C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                      C.sub.6 H.sub.5                                                                          Cl      CONHC.sub.2 H.sub.5                                                                             Cyan               118    C.sub.4 H.sub.9 OCH.sub.3                                                             C.sub.2 H.sub.5                                                                      C.sub.6 H.sub.5                                                                          2-NHCOCH.sub.3                                                                        CONHC.sub.7 H.sub.15                                                                            Cyan               119    C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                      C.sub.6 H.sub.5                                                                          3-Cl    Cl                Blue               120    C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                      Thien-2-yl 3-Cl    Cl                Cyan               121    C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                                                      Thien-3-yl 2-Cl    CONHC.sub.2 H.sub.5                                                                             Cyan               122    CH(CH.sub.3).sub.2                                                                    CH(CH.sub.3).sub.2                                                                    ##STR75## 2-CN    NHCOC.sub.2 H.sub.5                                                                             Cyan               123    C.sub.2 H.sub.5                                                                       C.sub.4 H.sub.9                                                                      Thien-3-yl 2-F     NHCOC.sub.4 H.sub.9                                                                             Cyan               124    C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                                                      C.sub.6 H.sub.5                                                                          H       CO.sub.2 C.sub.4 H.sub.9                                                                        Blue               125    C.sub.4 H.sub.9                                                                       C.sub.2 H.sub.5                                                                      C.sub.6 H.sub.5                                                                          H                                                                                      ##STR76##        Cyan               126    C.sub.3 H.sub.6 OC.sub.2 H.sub.5                                                      C.sub.4 H.sub.9                                                                      C.sub.6 H.sub.5                                                                          H                                                                                      ##STR77##        Cyan               127    C.sub.3 H.sub.7                                                                       C.sub.2 H.sub.5                                                                      C.sub.6 H.sub.5                                                                          H                                                                                      ##STR78##        Cyan               __________________________________________________________________________

EXAMPLE 128

The purity of hue of the dye of the formula ##STR79## was compared inmethylene chloride with that of the dyes of the formula ##STR80##disclosed in EP-A- 227 096. To this end, the brilliance (chroma),half-value widths of the main absorption band (HVW) and the hue (HGD)were determined by CIELAB within the lightness range L: 60<L<95. (Acomparison of different dyes is only meaningful if the lightness and hueare similar).

    ______________________________________                                        Dye No.                                                                              Chroma    HVW [nm]  L     HGD   λ.sub.max                       ______________________________________                                                                               [nm]                                   128a   66        109       70    223   625                                    128b   55        128       70    231   647                                    128c   61        123       70    223   665                                    ______________________________________                                    

The abovementioned values reveal the coloristic superiority of dye 128a.

Compared with the known dyes 128b and 128c, the novel dye 128a has amore steeply increasing absorption band and higher transparency in theblue and green region.

We claim:
 1. A thiazole dye of the formula I ##STR81## where R¹ and R²are identical or different and each is independently of the other, C₁-C₁₈ -alkyl, oxaalkyl having up to 18 carbon atoms and from 1 to 3oxygen atoms, alkanoyloxyalkyl having up to 18 carbon atoms oralkoxy-carbonyloxyalkyl having up to 18 carbon atoms, which may each besubstituted by phenyl, C₁ -C₄ -alkylphenyl, C₁ -C₄ -alkoxyphenyl,hydroxyl, cyclohexyl or cyano; hydrogen; unsubstituted or C₁ -C₄ -alkyl-or C₁ -C₄ -alkoxy-substituted phenyl; cyclohexyl or a radical of theformula

    (CH.sub.2 --).sub.k COO--(Y--O--).sub.m (W--O--).sub.v L.sup.1,

where k is 2, 3 or 4, m and v are identical or different and each is,independently of the other, 0, 1 or 2, Y and W are identical ordifferent and each is, independently of the other, C₂ -C₆ -alkylene andL¹ is C₁ -C₄ -alkyl or unsubstituted or C₁ -C₄ -alkyl- or C₁ -C₄-alkoxy-substituted phenyl,or R¹ and R², together with the linkingnitrogen atom, are a 5- or 6-membered saturated heterocyclic radicalwhich may contain one further oxygen or nitrogen hetero atom and besubstituted by C₁ -C₆ -alkyl, R³ is hydrogen, halogen, C₁ -C₈ -alkyl,unsubstituted or C₁ -C₄ -alkyl-or C₁ -C₄ -alkoxy-substituted phenyl,unsubstituted or C₁ -C₄ -alkyl- or C₁ -C₄ -alkoxy-substituted benzyl,cyclohexyl, hydroxyl, furyl or thienyl, and A is a radical of theformula ##STR82## where L² is hydrogen, fluorine, chlorine, bromine,hydroxyl, nitro, C₁ -C₄ -alkyl, cyano, C₁ -C₄ -alkyl-sulfonylamino or aradical of the formula COOR¹, CONHR¹, NHCOR¹ or NHSO₂ R¹, in each ofwhich R¹ is as defined above, andL³ is hydrogen, fluorine, chlorine,cyano or a radical of the formula CONHL⁴, NHCOL⁴, NHCONHL⁴, SO₂ NHL⁴,NHSO₂ L⁴ or COOR¹, where R¹ is as defined above and L⁴ is in each casealkoxycarbonylphenyl, alkoxycarbonyloxyphenyl, alkanoylphenyl orN-monoalkylcarbamoylphenyl, the alkyl moieties in these groups having upto 12 carbon atoms; phenyl; thiazolyl or C₁ -C₁₂ -alkyl, which may beinterrupted by from 1 to 3 oxygen atoms.
 2. A thiazole dye as claimed inclaim 1, having the formula II ##STR83## where R¹ and R² are each,independently of the other, C₁ -C₁₂ -alkyl, oxaalkyl having up to 12carbon atoms and from 1 to 3 oxygen atoms, alkanoyloxyalkyl having up to12 carbon atoms or alkoxycarbonylalkyl having up to 12 carbon atoms, ortogether with the linking nitrogen atom, a 5- or 6-membered saturatedheterocyclic radical which may contain one further hetero atom selectedfrom the group consisting of nitrogen and oxygen,L² is hydrogen or aradical of the formula CONHR¹, NHCOR¹ or NHSO₂ R¹, where R¹ is in eachcase as defined above, and L³ is a radical of the formula CONHL⁴,NHCOL⁴, SO₂ NHL⁴ or NHSO₃ L⁴,where R³ and L⁴ are each as defined inclaim
 1. 3. A process for transferring a merocyanine-like dye from atransfer to plastic-coated paper with the aid of an energy source, whichcomprises using a transfer on which there is or are situated one or morethiazole dyes of the formula I ##STR84## where R¹ and R² are identicalor different and each is, C₁ -C₁₈ -alkyl, oxaalkyl having up to 18carbon atoms and from 1 to 3 oxygen atoms, alkanoyloxyalkyl having up to18 carbon atoms or alkoxy-carbonyloxyalkyl having up to 18 carbon atoms,which may each be substituted by phenyl, C₁ -C₄ -alkylphenyl, C₁ -C₄-alkoxyphenyl, hydroxyl, cyclohexyl or cyano; hydrogen; unsubstituted orC₁ -C₄ -alkyl- or C₁ -C₄ -alkoxy-substituted phenyl; cyclohexyl or aradical of the formula

    (CH.sub.2 --).sub.k COO--(Y--O--).sub.m (W--O--).sub.v L.sup.1,

where k is 2, 3 or 4, m and v are identical or different and each is,independently of the other, 0, 1 or 2, Y and W are identical ordifferent and each is, independently of the other, C₂ -C₆ -alkylene andL¹ is C₁ -C₄ -alkyl or unsubstituted or C₁ -C₄ -alkyl- or C₁ -C₄-alkoxy-substituted phenyl,or R¹ and R², together with the linkingnitrogen atom, are a 5- or 6-membered saturated heterocyclic radicalwhich may contain one further oxygen or nitrogen hetero atom and besubstituted by C₁ -C₆ -alkyl, R³ is hydrogen, halogen, C₁ -C₈ -alkyl,unsubstituted or C₁ -C₄ -alkyl-or C₁ -C₄ -alkoxy-substituted phenyl,unsubstituted or C₁ -C₄ -alkyl- or C₁ -C₄ -alkoxy-substituted benzyl,cyclohexyl, hydroxyl, furyl or thienyl, and A is a radical of theformula ##STR85## where L² is hydrogen, fluorine, chlorine, bromine,hydroxyl, nitro, C₁ -C₄ -alkyl, cyano, C₁ -C₄ -alkyl-sulfonylamino or aradical of the formula COOR¹, CONHR¹, NHCOR¹ or NHSO₂ R¹, in each ofwhich R¹ is as defined above, andL³ is hydrogen, fluorine, chlorine,cyano or a radical of the formula CONHL⁴, NHCOL⁴, NHCONHL⁴, SO₂ NHL⁴,NHSO₂ L⁴ or COOR¹, where R¹ is as defined above and L⁴ is in each casealkoxycarbonylphenyl, alkoxycarbonyloxyphenyl, alkanoylphenyl orN-monoalkylcarbamoylphenyl, the alkyl moieties in these groups having upto 12 carbon atoms, phenyl, thiazolyl or C₁ -C₁₂ -alkyl, which may beinterrupted by from 1 to 3 oxygen atoms.